1. Field of the Invention
The present invention relates generally to the field of fluid coupling devices for selectively establishing a flow passage, and, more particularly, to an improved quick-disconnect coupling device having a rotating valve element in at least one of the coupling sections.
2. Description of the Prior Art
Many forms of fluid coupling devices have, of course, been heretofore developed. Some of these are of the quick-disconnect type, which facilitates interlocking and separation of male and female coupling sections.
It is also known to provide one or both of the coupling sections with a rotary ball valve, and to provide a mechanism for automatically rotating this valve from a flow-preventing position to a flow-permitting position when the male section is selectively inserted into the female section. In some of these known devices, a pin engages the ball valve at a location eccentric to the ball's center of rotation, to cause the ball to rotate as it is moved axially along the housing. However, because the ball rotated about its own center, it was necessary to accommodate relative motion between the pin and ball during such rotation. Such relative motion was typically accommodated by permitting linear motion of the ball relative to the pin, or the pin relative to the housing. Such prior art devices are shown, for example, in applicant's prior U.S. Pat. No. 4,473,211, and in U.S. Pat. Nos. 4,445,664, 4,181,149, 3,423,061, 3,618,892, 3,078,068 and 3,279,497.
It is also known that such coupling devices may have a substantially constant diameter flow passage therethrough, when the valve has been rotated to its flow-permitting position, so as to minimize the pressure drop across the coupling device. This is indicated in U.S. Pat. No. 3,078,068, and in applicant's prior U.S. Pat. No. 4,473,211.
However, upon information and belief, in all such prior art devices, the ball valve was caused to rotate about its center. This required a relatively high ratio of axial displacement per increment of valve rotation.